Oh, I am SO happy to see Tootsy's update! Very encouraging.
No, I have never seen side effects with the Mirtazapine. I have used it before with other pups. Sometimes it does not work....but, usually it does and the turn around can be dramatic. The first time I used it was with a renal failure pup who wouldn't eat a thing...within a day he was eating like a little piggy! I was shocked! Ask your vet about it....I am quite sure he will prescribe it. It usually works the same day...or at least after a couple of days.
Thank you for updating...please continue to keep us posted on your baby!